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B Pesson

Publications and source records attributed to B Pesson.

At least 19 recordsLinked to original sources
PubMed2006

Infection by Leishmania infantum in cats: epidemiological study in Spain.

More than 40 cases of feline leishmaniasis have been reported in the scientific literature. The influence of some immunodepressive conditions of viral origin, such as leukemia and feline immunodeficiency, are still unknown. The purpose of this study was to assess the prevalence of Leishmania infection in cats and possible relations with these viral infections. Markers of Leishmania infection were searched in 183 cats from Southern Spain by IFAT, PCR, Giemsa stain and culture, with a follow-up of positive cats. Seropositivity was 60.0% (Ab titer > or =10) and 28.3% of animals presented Ab titers > or =40. Around 25.7% of the cats studied were parasitemic and some of them remained positive for months. Combining both data, 70.6% of the feline population was, or could be, infected. We observed a negative association between seropositivity to Leishmania and infection by FeLV. Hence, production of antibodies against the parasite appears to be compromised in cats with leukemia, which have a prevalence of 36% in our study. In contrast, we found no association with feline immunodeficiency. The results makes us doubt the value of conventional serological methods to detect active Leishmania infection in cats.

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PubMed2005

Nocturnal activity of phlebotomine sandflies (Diptera: Psychodidae) in a cutaneous leishmaniasis focus in Chichaoua, Morocco.

The nocturnal activity of phlebotomine sandflies (Diptera: Psychodidae) was studied "at an epidemic focus" on human cutaneous leishmaniasis due to Leishmania tropica Wright in Chichaoua province, in Morocco. Sandflies were collected using light and sticky-paper traps changed at 2-h intervals, inside and around houses, in August and October 2004. Overall, 633 sandflies, belonging to six species of Phlebotomus and three of Sergentomyia, were collected. Sandfly activity was nocturnal and higher at twilight. Several activity patterns were observed according to the species. Phlebotomus (Paraphlebotomus) sergenti Parrot, 1917, the suspected vector of L. tropica in this focus, was caught during each collection performed from 1900 to 0500 hours, the numbers of species caught peaked at 1900-2100 hours. There were seasonal variations of the nocturnal activity, which could be related to the variations in temperature and relative humidity.

Animals↗
PubMed2005

Seasonal fluctuations of phlebotomine sand fly populations (Diptera: Psychodidae) in the urban area of Marrakech, Morocco.

Phlebotomine sand flies (Diptera: Psychodidae) were collected continuously, using sticky traps, during 1 year from October 2002 to September 2003, in an urban area of Marrakech city (Morocco). A total of 3277 specimens were collected belonging to five species. Phlebotomus (Phlebotomus) papatasi (54.6%) is the predominant species followed by Sergentomyia (Sergentomyia) minuta (20%), S. (S.) fallax (11.3%), P. (Paraphlebotomus) sergenti (10.3%) and P. (Larroussius) longicuspis (3.8%). Data analyses showed a mono-modal annual pattern for P. sergenti and a bi-modal one for the other species. P. papatasi, the proven vector of Leishmania major in Morocco, was active throughout the year. This species did not diapause in this region. P. papatasi population peaked in June and November, which relating to the periods of risk in this area. Its preferred temperature ranged between 32 and 36 degrees C but no significant correlation was found between its density and the temperature. Considering the high density and long activity period of P. papatasi, the area of Marrakech should be regarded as a potential focus for L. major. This suggests the need for a continuously surveillance to prevent risk of zoonotic cutaneous leishmaniasis.

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PubMed2005

Postglacial dispersal of Phlebotomus perniciosus into France.

Phlebotomus perniciosus was identified morphologically in samples from France and northeast Spain, and individuals were then characterized at three polymorphic isoenzyme loci (by isoelectrofocusing) and at the mitochondrial DNA locus (by comparative DNA sequence analysis of a fragment of the Cytochrome b gene). The four polymorphic loci gave conflicting patterns of population relationships, which can be explained by hypothesizing different amounts of gene introgression at each locus when two distinctive lineages met in southern France or northeast Spain after isolation in southern Italy and Spain during the Pleistocene Ice Ages. P. perniciosus is an important vector of leishmania infantum and so these population differentiation studies are relevant for predicting the emergence and spread of leishmaniasis in relation to environmental changes, including climate.

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PubMed2005

Entomological investigations in Chichaoua: an emerging epidemic focus of cutaneous leishmaniasis in Morocco.

Cutaneous leishmaniasis due to Leishmania tropica Wright seems to be an emerging disease in Chichaoua, a province located in southwestern Morocco. In this study, sand flies (Diptera: Psychodidae) were collected from 12 stations. Sticky traps were placed in domestic, peridomestic, and sylvatic sites. In total, 3,787 specimens consisting of 10 species (seven Phlebotomus and three Sergentomiya) were identified. Phlebotomus perniciosus Newstead, the predominant species, was abundant, especially in mountainous areas. Phlebotomus sergenti Parrot (12%) was found in all studied villages where it was associated with domestic and peridomestic habitats. On the basis of its abundance, distribution, and notable anthropophily, P. sergenti, a proven vector of L. tropica elsewhere, is considered the cutaneous leishmaniasis vector in this emerging focus.

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PubMed2005

Distribution of phlebotomine sandflies, of the subgenus Larroussius, in Morocco.

Adult sandflies (Diptera: Psychodidae) of the genus Phlebotomus and of the subgenus Larroussius were collected with sticky traps from thirty-four localities in central and south-western Morocco. Four Larroussius species were present in this area, Phlebotomus perniciosus Newstead, being the most widespread and abundant species particularly in the mountainous area, was sympatric with the closely related species Phlebotomus longicuspis Nitzulescu. Only one male of P. perniciosus displayed the bifid copulatory valves characteristic of the species. All specimens showed copulatory valves curved at their apex. The number of coxite hairs is a taxonomical tool that differentiates this morph of P. perniciosus from P. longicuspis. Phlebotomus ariasi Tonnoir was collected from six mountainous stations. Phlebotomus mariae Rioux et al. was scarce; only five males were collected and were often associated with P. ariasi.

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PubMed2004

Sandflies of the Phlebotomus perniciosus complex: mitochondrial introgression and a new sibling species of P. longicuspis in the Moroccan Rif.

The bloodsucking adult females of Phlebotomus perniciosus Newstead and P. longicuspis Nitzulescu (Diptera: Psychodidae) are important vectors of the protozoan Leishmania infantum Nicolle (Kinetoplastida: Trypanosomatidae) in western Mediterranean countries. The species status of the two phlebotomine sandflies was assessed, along with the epidemiological implications. Individual sandflies from three Moroccan Rif populations were characterized morphologically, isoenzymatically (by the isoelectrofocusing of alleles at the polymorphic enzyme loci of HK, GPI and PGM), and by comparative DNA sequence analysis of a fragment of mitochondrial Cytochrome b (mtDNA). By reference to the character profiles of specimens from other locations, including southern Spain and the type-locality countries, the Moroccan flies were placed in three lineages: first, the lineage of P. perniciosus, which contained two mtDNA sublineages, one (pnt) widely distributed and associated with the morphology of the male types from Malta, and the other (pna) associated with a P. longicuspis-like male morphology; second, the lineage of P. longicuspis sensu stricto, including typical forms from Tunisia; and third, a new sibling species of P. longicuspis. The mtDNA sublineage (pnt) of typical P. perniciosus was also found in some P. longicuspis from Morocco, indicating interspecific hybridization. The typical race of P. perniciosus occurs in Italy as well as in Malta, Tunisia and Morocco. It is replaced in southern Spain by the Iberian race (with the pni mtDNA sublineage). The discovery of interspecific gene introgression and a new sibling species mean that previous records of the two morphospecies do not necessarily reflect their true vectorial roles or geographical and ecological distributions.

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PubMed2002

Variation of esterase electromorphs associated with bloodmeal digestion in phlebotomine sand flies (Diptera: Psychodidae).

Esterases are often used to measure genetic variation, yet they may be influenced by external factors. Isoelectrofocusing was used to investigate the effects of bloodmeal on the esterase variation in wild populations of Phlebotomus (Larroussius) ariasi Tonnoir and P. (L.) perniciosus Newstead and in a colonized population of P. (Phlebotomus) duboscqi Neveu-Lemaire. Modified electrophoretic profiles were demonstrated to be associated with blood digestion. The bloodmeal-induced esterase electromorphs were only found in the abdomen homogenates of the sand flies. These changes in esterase phenotype were probably due to a proteolysis phenomenon and disappeared at the end of bloodmeal digestion. The effect was eliminated by adding trypsin inhibitors.

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PubMed2000

Phylogenetic analysis of Phlebotomus species belonging to the subgenus Larroussius (Diptera, psychodidae) by ITS2 rDNA sequences.

In the genealogy of Phlebotomus (Diptera: Psychodidae), morphological analyses have indicated that the subgenus Larroussius is a monophyletic group which is most closely related to the subgenera Transphlebotomus and Adlerius. We conducted a phylogenetic analysis of the relationships among six representative species of the subgenus Larroussius and one species representatitive of the Phlebotomus subgenus, assessing sequences of the Second Internal Transcribed Spacer (ITS2) of the ribosomal RNA (rRNA). Three of the species (P. perniciosus, P. ariasi and P. perfiliewi perfiliewi) were collected in different parts of the Mediterranean area. The trees estimated from parsimony and neighbour-joining analyses supported the monophyly of the Larroussius subgenus inferred from the morphological analysis. According to our data, P. ariasi may be a sister group to the rest of the Larroussius subgenus, although additional sequence data are needed to confirm this observation. Our results suggest that P. perniciosus and P. longicuspis are distinct species, in spite of the fact that there are only slight morphological differences. The strict congruence between the phylogeny of the Larroussius subgenus inferred from the ITS2 sequences and that based on morphological studies further confirmed the ability of the spacer sequence to identify recently-derived affiliations.

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PubMed2000

Genetic polymorphism in sympatric species of the genus Phlebotomus, with special reference to Phlebotomus perniciosus and Phlebotomus longicuspis (Diptera, Phlebotomidae).

The Random Amplified Polymorphic DNA assay was used to study genetic variation within and between five Phlebotomus species belonging to three subgenera: P. (Larroussius) ariasi, P. (L.) longicuspis, P. (L.) perniciosus, P.(Paraphlebotomus) sergenti and P. (Phlebotomus) papatasi sympatric in southern Spain and proven vector of leishmaniasis. Two cluster analysis were proposed: one according to sandfly species and populations, the second according individual specimens of Phlebotomus perniciosus, Phlebotomus longicuspis s.l. and intermediate morphological specimens between these species. The results obtained are closely correlated with the taxonomy classically accepted for the subgenera and with the automatic classifications made by other authors which use morphological and isoenzymatic data. The validity of the species Phlebotomus longicuspis is also discussed.

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PubMed2000

Electrophoretic and morphological differentiation between two sympatric species of Adlerius: Phlebotomus brevis and Phlebotomus simici (Diptera: Psychodidae).

Phlebotomus simici Theodor and P. brevis Artemiev & Dergacheva are closely related species in the subgenus Adlerius that only may be identified by the male terminalia. Females only may be differentiated by collecting them in copula. Because females of P. simici may be involved in Leishmania transmission, their identity should be verified. Our study separated individual from 2 sympatric populations in Lebanon by means of agarose enzyme electrophoresis. Differential patterns were found at the PGM and HK loci. Results were confirmed by morphological reexamination of female spermathecae and pharyngeal armature.

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PubMed1999

Morphological and isoenzymatic differentiation of sympatric populations of Phlebotomus perniciosus and Phlebotomus longicuspis (Diptera: Psychodidae) in northern Morocco.

The phlebotomine sandfly Phlebotomus perniciosus Newstead is a vector of Leishmania infantum Nicolle in the western Mediterranean basin. In northern Morocco it is often caught in sympatry with a closely related species, P. longicuspis Nitzulescu. In the locality of Chefchaouene where females of both species were morphologically distinguishable, none of the collected males exhibited forked copulatory valves, which is considered a specific character for P. perniciosus. They 1st were identified as P. longicuspis. Isoelectrofocusing of 7 enzyme systems was used to compare these specimens with the sympatric females. Two groups of males were separated and assigned to each species by their isoenzyme patterns associated with morphological differences in the shape of the aedeagus and in the number of coxite hairs. Based on our results, a reexamination of the distribution of both species is necessary especially in many locations where P. longicuspis has been identified only from males.

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PubMed1996

Phlebotomus sergenti parrot, 1917: morphological and isoenzymatic comparisons of two natural populations from Tenerife (Canary Islands, Spain) and Crete (Greece).

Samples of two Phlebotomus sergenti natural populations from San Juan (Tenerife), representing the western edge of the distribution area of this species, and Axos (Crete) were collected. The morphological comparison showed marked differences in the lengths of parts of the male genitalia, female pharynx, and spermathecae. The isoenzyme study revealed characteristic monomorphic phenotypes for glucose phosphate isomerase, hexokinase, and phosphoglucomutase in the Canarian specimens as compared with the Cretan population. These results confirm the heterogeneity of P. sergenti and indicate the utility of a systematic double approach for a revision of this taxon.

Animals↗
PubMed1996

Differentiation of females in Sergentomyia sensu stricto (Diptera: Psychodidae) using scanning electron microscopy of pharyngeal armatures.

Scanning electron microscopy of external ornamentation and internal armature of the pharynx was used to identify females of Sergentomyia sensu stricto. Five species from the eastern Mediterranean basin were compared; S. minuta clearly was separated from species of the fallax-group. Within the fallax-group, S. fallax was distinguished readily by its heart-shaped pharynx and the difference in armature between the dorsal and lateral plates.

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PubMed1994

The armature in the genital atrium as a new taxonomic character distinguishing females of Phlebotomus papatasi and P. duboscqi (Diptera: Psychodidae).

Descriptions are given of armatures in the genital atria of females of the two morphologically similar sandfly species, Phlebotomus papatasi and P. duboscqi. The species are distinguishable by the size and shape of the armature, the grouping of the spines in the armature and the length and shape of the spines. These characters have been shown to separate females of other closely related species of phlebotomine sandflies.

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